System of Measurement Inch Heavy Hex Bolt Head Type - Bolts Hex Basic Material Steel Material Grade A307B Fastener Finish Plain Dia./Thread Size 5/8 In.-11 Fastener Length 3 in Fastener Thread Direction Right Hand Fastener Thread Type UNC (Coarse) Fastener Industry Standards ASME B18.2.1 Min Thread Length 1 1/2 in Fastener Thread Style Partially Threaded Head Height 27/64 in Head Width 1 1/16 in Package Quantity 10